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An Inner Molecular Bar or Disk in NGC 5195

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 نشر من قبل Susanne Aalto
 تاريخ النشر 2001
  مجال البحث فيزياء
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High resolution OVRO CO 1-0 observations of the inner kpc of the M51-companion NGC 5195 reveal the presence of a kpc-sized bar, or possibly an inclined disk with a two armed spiral, at the center of the optical bar. The molecular mass of the feature is 2.7 x 10^8 M_o, half of which is within a radius of 250 pc. The resulting gas surface density of 10^3 M_o pc^-2 is typical for starbursts. However, the lack of evidence for current star formation suggests that either some mechanism is preventing stars from forming, or the standard CO to H_2 conversion factor substantially overestimates the available amounts of molecular gas.



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